In a mobile phone, which is a type of electronic equipment, a liquid crystal display device for informing a variety of information to the user by means of characters and images is mounted. In a foldable mobile phone A as shown in FIG. 19 and FIG. 20, a liquid crystal display device E is accommodated in the inside of an upper cabinet D which is connected to a lower cabinet B having a variety of controllers by means of a hinge C.
The liquid crystal display device E together with a backlight device G is mounted, through a holder H, on a circuit board F disposed in the upper cabinet D that comprises an upper inner casing Da and an upper outer casing Db. In the upper inner casing Da, a viewing window Do which is faced with the display screen Ef of the liquid crystal display device E is formed. In the viewing window Do, a display screen protection cover I made of a light transmitting material is mounted.
In general electronic equipment, the equipment cabinet is made of a plastic material for the purposes of reduction in weight, etc. With the mobile phone A described above in which a large viewing window Do is formed in the upper inner casing Da, the upper inner casing Da is likely to be deflected or deformed relatively easily when the display screen protection cover I is heavily depressed from the outside, which may cause the display screen protection cover I to be brought into contact with the liquid crystal display device E, resulting in that damages such as cracks are created in the display device E.
Possible solutions to such a problem are to increase the wall thickness of the upper cabinet D including that of the upper inner casing Da thereby enhancing the strength, or to increase the clearance between the display screen Ef of the liquid crystal display device E and the display screen protection cover I. However, these solutions inevitably cause another problem of an undesired increase in the size of the mobile phone A.
On the other hand, a solution which increases the mechanical strength of the equipment cabinet has been proposed in which the equipment cabinet made of a plastic material is integrally molded with the reinforcing member made of a metallic material.
Specifically, as shown in FIG. 21, an upper inner casing Da′ accommodates, together with an upper outer casing Db′, a liquid crystal display device E′ which is loaded on a circuit board F′ through a holder H′. A display screen protection cover I′ is mounted in a viewing window Do′ of the upper inner casing Da′ and a pair of hinges C′ are provided at the base side end of the upper inner casing Da′. Further, the upper inner casing Da′ is integrally molded with a reinforcing member J as shown in FIG. 22 in the injection molding.
The reinforcing member J has a top plate Ja in which an opening Jo is formed corresponding to the viewing window Do′ in the upper inner casing Da′. A pair of side plates Jb are erected from the right and left edges of the top plate Ja, and a pair of bearing members Jc which have a cylindrical shape are formed at the base side end of the top plate Ja.
According to this configuration, the mechanical strength of the upper inner casing Da′ is greatly improved because it is integrally formed with the reinforcing member J. With this configuration, even if the display screen protection cover I′ is heavily pressed from the outside, the upper inner casing Da′ will not be easily deflected or deformed. Thus, damage to the liquid crystal display device E′ due to the contact with the display screen protection cover I′ can be prevented.
However, with the configuration as described above, although the mechanical strength of the upper inner casing Da′ is improved, the reinforcing member J occupies a significantly large portion of the inside of the upper inner casing Da′ as shown in FIG. 23. Therefore, the size of the outline shape is inevitably increased.
Further, with the configuration as described above, the top plate Ja, the right and left side plates Jb, and the pair of bearing members Jc are provided, thus the reinforcing member J is integrally insert molded with the upper inner casing Da′ over the entire area of the upper inner casing Da′, which results in an increase in the rigidity of the upper inner casing Da′ as a whole, which leads to an increase in the rigidity of the upper cabinet including the upper inner casing Da′.
Therefore, even if the display screen protection cover I′ is heavily pressed from the outside, damage to the liquid crystal display device E′ can be prevented. However, because the upper cabinet has a high rigidity and lacks the flexibility as stated above, when the upper cabinet is subjected to a great impact force due to such a cause as dropping, the impact force is neither absorbed nor attenuated by the upper cabinet, but directly acts on the liquid crystal display device E′. As a result, the liquid crystal display device E′, which comprises a glass substrate, and the plastic material portion itself of the equipment cabinet may be cracked or otherwise damaged.